<template>
  <div class="app-container">
    <el-input
      v-model="filterText"
      placeholder="Filter keyword"
      style="margin-bottom: 30px"
    />

    <el-tree
      ref="tree2"
      :data="data2"
      :props="defaultProps"
      :filter-node-method="filterNode"
      class="filter-tree"
      default-expand-all
    />
  </div>
</template>

<script>
import subject from "@/api/edu/subject"

export default {
  data() {
    return {
      filterText: '',
      data2: [],
      defaultProps: {
        children: 'children',
        label: 'title'
      }
    };
  },
  created() {
    this.getAllSubjectList()
  },
  watch: {
    filterText(val) {
      this.$refs.tree2.filter(val)
    }
  },
  methods: {
    getAllSubjectList(){
      subject.getSubjectList()
          .then(response =>{
            this.data2 = response.data.list
          })
    },
    filterNode(value, data){
      if(!value) return true
      // 不区分大小写，所以都转为小写
      return data.title.toLowerCase().indexOf(value) !== -1
    }
  }
};
</script>